package no17;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class FailFast {
	public static void main(String[] args) {
		//两个引用同时修改一个List
		List<String> list = new ArrayList<String>();
		Iterator it = list.iterator();
		list.add("a");
		it.next();
	}
}
